Continuous ambulatory peritoneal dialysis (CAPD) is a commonly used therapeutic technique which has the advantage of allowing a patient to perform dialysis without recourse to a hospital or other clinical facility. Basically, a catheter is implanted in the patient, and apparatus is connected to this catheter for introducing dialysis fluid into the peritoneal cavity and withdrawing it therefrom after dialysis has taken place. The procedure involves the connection of the patient's catheter to, and its disconnection from, various fluid containers in the course of a fluid exchange.
Because the procedure is normally carried out by the patient himself in a septic environment, great caution must be exercised to prevent contamination of the dialysis fluid with bacteria capable of causing peritonitis. Indeed, statistical studies show that CAPD patients using some prior art exchange devices contract peritonitis on the average of once every four months whereas patients undergoing the very similar continuous cycling peritoneal dialysis therapy (CCPD), which is performed in a clinical environment, contract peritonitis only about once every two years on the average.
There consequently exists a need for a fluid exchange apparatus for CAPD in which there is a minimum chance of contamination of any fluid-contacting surfaces by the patient's hands, the furniture in the room, or airborne bacteria.
In a widely used prior art device, a fluid exchange involves the drainage of spent dialysis fluid into a used-fluid bag; the disconnection of a needle-shaped connector from the used-fluid bag; the insertion of the connector into a fresh-fluid bag; and the drainage of the fresh fluid into the patient's peritoneal cavity. During the switch from the used-fluid bag to the fresh-fluid bag, careless patients were frequently tempted to momentarily set the connector down on a septic work surface where it would become contaminated. Bacteria deposited on the tip of the connector would then be flushed into the peritoneal cavity during the infusion of the fresh dialysis fluid.
It was subsequently proposed to provide a system in which the used-fluid container and the fresh-fluid container were aseptically connected to a single, valved system prior to the exchange. The assembled aseptic system was then connected to the patient's catheter in a single motion, and remained so connected throughout the exchange. Following the exchange, the patient's catheter was capped with an aseptic cap. Connectors with recessed, shrouded conduits mated by a luer taper were used to minimize the chance of the patient's hands contacting elements of the fluid path.
In order to hold the system connector in an aseptic condition until it was ready to be connected to the patient's catheter, it was next proposed to provide a holder which could be adhesively secured to a work surface, and which held the system connector in an aseptic condition until ready for use. The holder also held a cap in contact with a sponge. During the fluid drainage or infusion (which takes some time), the cap could be lifted off the holder, the sponge could be saturated with a sterilant, and the cap could then be replaced onto the sponge so as to coat with sterilant at least some of the portions of the cap which would eventually be inserted into the patient's catheter connector.
Although the last-mentioned arrangement assured a substantial amount of sterility, there was still a chance of contamination of some interior portions of the cap which were not reached by the sterilant. It was therefore desirable to provide a holder in which sterilant could not only be added to the cap without removing the cap from the holder, but in which the sterilant would also coat virtually all of the interior surfaces of the cap.